In addition, the NGS examination based on MYSTIC trial (Rizvi et al. 2020) revealed that ARID1A mutations are associated with improved outcomes with the PD-1 inhibitor durvalumab plus the CTLA4 inhibitor tremelimumab reported by Rizvi NA, et al. Based on these studies for new biomarkers of cancer immunotherapy especially for ARID1A mutations, we conducted our research in order to further investigate the significance of ARID1 mutations, including ARID1A and ARID1B, in predicting the prognosis of ICIs treatment for advanced NSCLC. The gene discussed is CTLA4; the disease is cancer.